Heat retaining device for window structures



July 30, 1935.

J. M. FLANAGAN4 'HEAT RETAINING DEVICE FOR WINDOW STRUCTU RES Filed Dec. 17, 1932 3 W0 cam M conductor of heat. perature diiferential between the inside and out- Patented July 30, 1935 UNITED S A E P ENT/ FICE 1 EA aa'rammonnvros Foa-wmnow smoo'ronas JohnM Flanagan, Scarsdale, N. Y. Application December 17, 1932. Serial No. 647,811 2 Claims. (oi. 29-40) v This invention relates to window structures and has particular reference to an arrangement which will overcome, orat least minimize, the transfer of heat between the interior of a building structure and the outside. Itis frequently diflicult, particularlyin' extremely cold weather, to maintain a room, glassed-in porch or the like at a proper temperature. The difiiculty increases to-a large extent the greater the number of windows, indicating that the windows are'responsible for heat losses. There is, of course, some'loss of heat due to the leakage of cold air. from the outside between the movable portions of the window structure, which, however, may to a large extent be overcome by'precisely fitting the various parts or by the use of weather stripping. On the other hand, even where the latter precautions are taken there is a transfer of heat between the inside and outside by a conduction'through the window, due to the fact that while the coeflicient of heat conductivity of, glass is not as high as in many materials, the glass is nevertheless a relatively good Hence, where there is a temside of a window, there will be a constant flow of heat by conduction through the window glass.

The essential object of the present invention is to overcome the difiiculties just referred to so as to make it possible to maintain a building structure at a desired temperature. Such result is obtained by the provision of a screen, in association with the window structure, of transparent and clear material so as not to interfere with the transmission of light, and so arranged that the transfer of heat through or around the window structure will be substantially reduced. The screen will desirably comprise material such as cellophane which has a relatively low coeflicient of heat conductivity so that the transfer of heat therethrough by conduction will be as low as possible. It is particularly desirable that the conductivity of the screen be less than that of ordinary window glass for best results. The screen may be mounted on the inner side of the window, and in such arrangement will substantially reduce heat losses in that the heated air within the building structure will not come in direct contact with the window glass, and the only heat transmitted through the glass is such as first passes through the screen. The benefits to be derived increase, the lower the coefficient of conductivity of the material of which the screen is composed.

In order to give access to the window the heat retaining screen should be removable. Desirably the same will be associated with thei window frame so that when in position'it willi'orm a tight fit therewith, but so amounted that it may be-withdrawn. The use of-cellophane for the screen is desirable because such material is flexible, and 5 the screen may therefore be mounted on a roller in. the :manner of the ordinary window shade so that the'screen may be drawn down into opera- .tive position or quickly rolled up when its usev is not desired. I do not limit myself to ascreen of cellophane, as it is obviousrthat various other transparent, clear and flexible materials-will be equally suited to my purpose. a

From the description just given it will be apparent to those skilled in the art that, my invention may take-various forms and I therefore do not limit myself, to any specific arrangement of .parts. I have, however, in the accompanying drawing illustrated one practical embodiment of my invention which will function asre- .quired and wherein:

Fig. 1 is a plan view of a window structure illustrating the application of my invention;

Fig. 2 is a view in sectional elevation taken on the line 2-2 of Fig. 1;

Fig. 3 is an enlarged fragmentary view taken on the line 3-3 of Fig. 1.

In the figures the reference numeral 40' designates, generally, a window frame in which may be mounted one or more panes of glass I I in any well known manner. Presumably, the panes will be mounted in movable sashes, but this is immaterial so far as my invention is concerned, and likewise it is of no consequence whether the sashes be of the sliding or swinging type.

In association with the window structure I provide a transparent, clear screen l2 disposed on the inside of the window structure which, as illustrated, may be supported at its edges by the window frame in such manner as to prevent air circulating on the inside from comingin contact with the window glass, and, in effect, there-' fore providing a heat-retaining shield between the window and the interior of the structure in which it is located.

By utilizing flexible, clear, transparent material for the screen l2, the same may be readily removed but capable of being quickly brought again into operative position by mounting the same on a roller l3 located at the top of the window frame III in a manner similar to that of conventional window shades. Where such arrangement is resorted to it is advisable in order that the screen operate efliciently to prevent heat losses that provision bemade to prevent the passage and circulation of air around the edges of the screen and into contact with the glass. To this end means are provided along the sides and bottom of the window frame to engage the edges of the screen. Along the bottom of the frame a strip ll of soft rubber, felt or other yieldable material is provided, with which the lower edge of the screen may be made to firmly contact by stiffening and strengthening the edge with a strip of wood or other material,- as indicated by the reference numeral l5. Along the sides of the window frame, as shown in Figure- 3, are provided channel members It in which the edges of the screen will slide. 'To insure a more air-tight flt the channel members may be provided with a liner I! of soft material such as felt which will contact without injuring the edges of the screen. If desired the channel structure may be utilized also along the sill of the frame in lieu of the arrangement above described.

By arranging the screen I: in spaced relation to the glass ,as shown in Figures 2 and 3, and by the arrangement which provides intimate association between the frameand the screen, an additional advantage is gained in preventing the transfer of heat between the inside-and outside of the window structure in that' a dead air space 18 is provided which, due to the poor conductivity of air, will act as a further shield additional to the screen.

It will thus be seen that I have provided a simple, inexpensive and efllcient structure calculated to overcome various objectionable features' of ordinary window structures. In cutting down the transfer of heat through windows between the inside and outside, my invention enables building structures to be maintained more readily at a desired temperature with accompanying conservation of fuel. In addition to being useful to retain heat in a building in coldweather, the arrangement described may function also in warm weather to prevent the transfer of heat from the outside to the inside. The device possessesobvious advantages over so-called storm windows, among which may be mentioned the ease with which it may be removed or brought into use.

I claim:

1. A device to prevent the dissipation or absorption of hot and cold air through glass windows which comprises, in combination with a window supporting frame, a transparent screen of flexible sheet material retractably supported in spaced relation with the window at one end 'of the frame and extendable over the window to completely cover the area defined by the supporting frame, and channel members extending along the side portions of said frame adapted to engage the side edges of the transparent flexible screen when extended, said channels presentin'g felt surfaces making bearing contact with the edges of the screen and forming a' substantiallyair-tight connection between the screen and theframe. 2. A device to prevent the dissipation or absorption of hot and cold air through glass windows which comprises, .in. combination with a window supporting frame, atransparent screen of flexible sheet material'retractably supported in spaced relation with thewindow at one end of the frame and extendable over the window to completely cover the area defined by the supporting frame, and means around said frame adapted to engage the edges of the transparent flexible screen when extended and forming a substantially air-tight connection between the screen and the frame including guideways extending along the opposite sides of the frame presenting surfaces which press against the surface of the screen at its edges.

' JOHN M. FLANAGAN. 

